1. Field of the Invention
The invention relates generally to host bus adapter (HBA) for coupling a host computer system to peripheral devices and more specifically relates to an HBA that couples both Fibre Channel (FC) and Serial Attached SCSI (SAS) storage device to a host computer system.
2. Discussion of Related Art
Fibre Channel has been a common standard for coupling of storage devices to a computer system for high speed applications. SAS has been evolving as a lower cost alternative to Fibre Channel providing similar performance at lower costs. Further, using a SAS connection, still lower cost Serial Advanced Technology Attachment (SATA) storage devices may be used by utilizing the SATA Tunneling Protocol (STP) in the SAS family of protocols.
Some computing environments are migrating new storage applications to lower cost SAS/SATA architectures but still must support older, legacy storage applications operating on FC storage devices coupled through an FC communication medium. In such cases, a computing system must provide two HBAs—one for coupling to the SAS/SATA storage devices and another for coupling to the FC connected storage devices. Use of two HBAs consumes resources in the computing system and complicates software applications that may require access to both the SAS/SATA storage devices and the FC storage devices.
Thus it is an ongoing challenge to simplify structures to support both FC and SAS/SATA storage devices on a single computing system.